Author Topic: grooves for PP bullets (Read 1075 times)

bufflernickl · « **on:** March 06, 2006, 02:35:10 AM »

I'm thinking about rifling a BOCR barrel myself for use with PP bullets. This would be in the .38=.40 cal range. I've read Matthews and searched a few forums, but have never found a definitive ideal groove form stated. It seems that most folks think around .008" total depth for both grooves because that's what they have. But, what if you could make them any depth, width, etc. What would be best???

TIA/buffler

Woodbutcher · « **Reply #1 on:** March 12, 2006, 12:54:21 PM »

I've been waiting for a response to this question too. I guess the rifle used will have to provide the answer. Woodbutcher

JBMauser · « **Reply #2 on:** March 13, 2006, 05:55:43 PM »

My gut tells me there is no answer to your question as asked. A paper jacket needs to be very close to the the difference in groove to bore. the best (I have read) results are when the rifling just engraves the pill. Then you have to decide wether the "system" you are building needs to cut the paper so that it is stipped away neatly a few yards down range or stays put to impact. You are correct that there is some optimum rifling between that of a Wittworth and a micro grove. But since you are looking to build a system with a paper jacket, I think you have to put those variables into the mix if you are asking for a measurement of one factor. JB

Lead pot · « **Reply #3 on:** March 14, 2006, 04:17:30 AM »

If I had a way to rifle a barrel for PP I would make it a 3 groove with lanz and groove of equal width at .006 deep.

Kurt